In wireless communication systems, a signal transmitted through a wireless channel may be severely distorted because of interference, noise, and multi-path fading. The most severe distortion comes from multi-path fading. For example, a signal may not travel in a direct line-of-sight (LOS) path from the transmitter to the receiver. Instead, the signal may travel in a longer path after being reflected and/or refracted by objects such as vehicles, buildings, and mountains, before reaching the receiver. Thus, the receiver may receive multiple delay versions of the signal.
In a direct-sequence (DS) code division multiple access (CDMA) communication system, for example, a rake receiver is a common demodulation technology used to mitigate such distortion and to select the relevant signals from all other received signals. Conventional rake receivers are typically implemented digitally and include numerous logic gates and discrete memories. In particular, rake receivers include a number of rake fingers (i.e., correlators) to process the multiple paths of a multi-path signal. For example, a rake receiver integrated within a mobile station may include three (3) rake fingers whereas a rake receiver integrated within a base station may include four (4) or five (5) rake fingers. Accordingly, manufacturing cost of mobile stations and base stations using conventional rake receivers are increased. Therefore, a need exists to reduce the manufacturing cost of the receiving unit integrated into mobile stations and/or base stations.